4127 Segmentation fault "$BIN2LLVMIR" "${BIN2LLVMIR_PARAMS[@]}" -o "$OUT_BACKEND_BC"

[kolomparrudi]

Hi,

I'm trying to decompile a windows C++ executable and got this error:

Decompiling /root/sample.exe into /root/sample.c.backend.bc...

RUN: /usr/local/bin/retdec-bin2llvmir -provider-init -decoder -verify -main-detection -idioms-libgcc -inst-opt -register -cond-branch-opt -syscalls -stack -constants -param-return -local-vars -inst-opt -simple-types -generate-dsm -remove-asm-instrs -class-hierarchy -select-fncs -unreachable-funcs -inst-opt -value-protect -instcombine -tbaa -targetlibinfo -basicaa -domtree -simplifycfg -domtree -early-cse -lower-expect -targetlibinfo -tbaa -basicaa -globalopt -mem2reg -instcombine -simplifycfg -basiccg -domtree -early-cse -lazy-value-info -jump-threading -correlated-propagation -simplifycfg -instcombine -simplifycfg -reassociate -domtree -loops -loop-simplify -lcssa -loop-rotate -licm -lcssa -instcombine -scalar-evolution -loop-simplifycfg -loop-simplify -aa -loop-accesses -loop-load-elim -lcssa -indvars -loop-idiom -loop-deletion -memdep -gvn -memdep -sccp -instcombine -lazy-value-info -jump-threading -correlated-propagation -domtree -memdep -dse -dce -bdce -adce -die -simplifycfg -instcombine -strip-dead-prototypes -globaldce -constmerge -constprop -instnamer -domtree -instcombine -instcombine -tbaa -targetlibinfo -basicaa -domtree -simplifycfg -domtree -early-cse -lower-expect -targetlibinfo -tbaa -basicaa -globalopt -mem2reg -instcombine -simplifycfg -basiccg -domtree -early-cse -lazy-value-info -jump-threading -correlated-propagation -simplifycfg -instcombine -simplifycfg -reassociate -domtree -loops -loop-simplify -lcssa -loop-rotate -licm -lcssa -instcombine -scalar-evolution -loop-simplifycfg -loop-simplify -aa -loop-accesses -loop-load-elim -lcssa -indvars -loop-idiom -loop-deletion -memdep -gvn -memdep -sccp -instcombine -lazy-value-info -jump-threading -correlated-propagation -domtree -memdep -dse -dce -bdce -adce -die -simplifycfg -instcombine -strip-dead-prototypes -globaldce -constmerge -constprop -instnamer -domtree -instcombine -simple-types -stack-ptr-op-remove -inst-opt -idioms -global-to-local -dead-global-assign -instcombine -phi2seq -value-protect -disable-inlining -disable-simplify-libcalls -config-path /root/sample.c.json -max-memory-half-ram -o /root/sample.c.backend.bc
Running phase: Initialization ( 0.01s )
Running phase: LLVM ( 0.02s )
Running phase: Providers initialization ( 0.02s )
Running phase: Input binary to LLVM IR decoding ( 0.85s )
/usr/local/bin/retdec-decompiler.sh: line 1264: 4127 Segmentation fault "$BIN2LLVMIR" "${BIN2LLVMIR_PARAMS[@]}" -o "$OUT_BACKEND_BC"
Error: Decompilation to LLVM IR failed

Tried to run from gdb for backtrace:

Running phase: Initialization ( 0.01s )
Running phase: LLVM ( 0.02s )
Running phase: Providers initialization ( 0.02s )
Running phase: Input binary to LLVM IR decoding ( 0.86s )

Program received signal SIGSEGV, Segmentation fault.
0x000055555596d7fb in cs_disasm_iter ()
(gdb) bt
#0 0x000055555596d7fb in cs_disasm_iter ()
#1 0x000055555595370d in retdec::capstone2llvmir::Capstone2LlvmIrTranslator_impl<cs_x86, cs_x86_op>::translateOne(unsigned char const*&, unsigned long&, retdec::utils::Address&, llvm::IRBuilder<llvm::ConstantFolder, llvm::IRBuilderDefaultInserter>&) ()
#2 0x00005555557e71a7 in retdec::bin2llvmir::Decoder::translate(std::pair<unsigned char const*, unsigned long>&, retdec::utils::Address&, llvm::IRBuilder<llvm::ConstantFolder, llvm::IRBuilderDefaultInserter>&) ()
#3 0x00005555557eb670 in retdec::bin2llvmir::Decoder::decodeJumpTarget(retdec::bin2llvmir::JumpTarget const&) ()
#4 0x00005555557ebd9b in retdec::bin2llvmir::Decoder::decode() ()
#5 0x00005555557ec32d in retdec::bin2llvmir::Decoder::runOnModule(llvm::Module&) ()
#6 0x0000555556216e24 in llvm::legacy::PassManagerImpl::run(llvm::Module&) ()
#7 0x0000555555788dc0 in _main(int, char**) ()
#8 0x0000555555641aa6 in main ()

[PeterMatula]

Are you using the current master or pre-built package? It maybe have been fixed in master, but I cannot check it without the input binary. We should release a new version in a few days, so you can try it then.

[kolomparrudi]

Hi,

Used the latest master. Also tried a windows prebuilt binary with same results. Tried also with IDA plugin, a selective decompile and it worked.

[PeterMatula]

1. Can you share the sample? If I was able to reproduce the problem, It would probably be an easy and fast fix.
2. If not, more precise backtrace could help - build RetDec in debug mode (-DCMAKE_BUILD_TYPE=Debug on linux, --config Debug on Windows) and re-run the gdb. Also, if you are on Linux, send a valgrind log as well.

[PeterMatula]

Closing the issue, since I cannot reproduce this without a binary or gdb backtrace.